Method of and apparatus for deriving alpha constant current



March is 926, 1,577,248

s. COHEN I METHOD OF AND APPARATUS FOR DERIVING A CONSTANT-CURRENT Filed April '18 11 4 I Lay INVENTbR BY W ATTORNEYS Patented Mar. 16, 1926.

} UN TE Fs'r res I SAMUEL COHEN, OF BROOKLYN, NEW YORK.

- METHOD OF AND APPARATUS FOR DERIVING A CONSTANT CURRENT.

Application filed April 18, 1924. .Serial No. 707,372.

'To all whom it may concern Be it known that I, SQIUEL Conner, a citizen of the Umted Statcs, residing at Brooklyn, in the county of Kings,' cityand State of New York, have invented certain new and useful Improvements in Methods of and Apparatus for Deriving a Constant Current, of which the following is a specification. I

This invention relates to a new and improved method of and apparatus .for deriving a constant current from a source of pulsating or alternating current.

One of the objects of my invention is to provide a simple and efficient method of so deriving. a. constant currentwith eitherno-variation at all or with a variation which is so negligible that the saidcurrcnt can be used in radio receiving circuits to serve as a substitute for the current at present derived either from the A battery or from i the B battery.

' "Another object of my invention'is to provide a method and means of the kind above described which will obviate the necessity of using filters and all complicated and expensive apparatus.

Another object of my invention is to provide an apparatus and a device of the.kind above specified which will 'give a uniform and .eflicient action at all times.

. Other objects of my invention will be set forth in the following description andin the drawing which diagrammatically illustrates a preferred embodiment of my invention.

. A source of alternating or pulsating cur rent is connected tothe terminals of the primary transformer T which can be of any -ordinary type. A I 1 The secondary coil of the transformer T is connected to the load H by means of. a

rectifier R, a regulating resistance R, and' by means of a pluralityof sections each of which-'isdesi'gnedto receive and transmit the desired current pulse and toalso receive and suppress. or by-pass any undesirable currentpulse so that by the use of a sufficient number of sections the load H receives only a substantially uniform direct current.

The current pulses formed in the second ary. of the transformer T are first passed through a rectifier B. This rectifier R can be of any desired type and it maybe either electrolytic or electronic in its action. The action of the rectifier is to interpose much greater resistance to one pulse of the current than to the-other pulse thereof and this'is indicated in the diagrannnatic draw ing to show that normally the upper wire of the receiving line is negative in value. However, no rectifier has as yet been made which co'mpletel y suppresses one or more of the pulses of the alternating current formed in the secondary coil of the'transformer and it is therefore necessary, to secure the results before mentioned, to suppress the undesired current pulse or pulses after they have passed through the rectifier. The current component which is to be utilized for the load H may for convenience be called the load component and the other components may be called the non-load components. The load component is either non-pulsating or it has a much lower frequency than the non-'- load components. The receiving lines or mains have a series of inductances L L L L L andL which are symmetrically arranged. These inductances are preferably- 1 of equal value and are preferably made with acid solution or steel nickel. electrodes immersed in the well known alkaline solution.

Each electrolytic condenser E may be formed of any desired number of such cells since the number of such cells presentiin each condenser E depends upon the voltage desired for the load H. I I 4' If a higher voltage is required for the load then a greater number of cells for each condenser E is required.

The action of the said electrolytic condensers is to accumulate the'load currentcomponent sent to them through the preceding inductance and to transmit the accumulated charge tothesucceedirig pair of inductances.

In order to suppress any undesired cur rent pulse, electrostatic condensersOare shunted across the line between the inductance sections so that the electrolytic condensers and the electrostatic condensers alternate. These condensers C should be made strong enough to resist any applied voltage and each condenser C is grounded as shown, the grounded connection being made .to the common junction.

Since the impedance of each electrostatic condenser C is infinite fora direct current v any high frequency alternating current in the receiving line is shunted and caused to leak out of the hue while the load com.- ponent of the current in the receiv ng line is sent on to the next section.

The respective electrolytic condensers E each preferably have the same number of cells and they are arranged 'so as to. have the same relative polarityas shown in the drawing.

If desired, the point G of the circuit may be grounded and it is'then unnecessary to ground the electrostatic condensers C as shown in the drawing.

The load voltage maybe controlled by regulating the line current by means of the resistance or rheostat R. The rheostat R can also be utilized forregulating the uniformity of the load voltage and this is accomplished by regulating the charging current to the condensers E. i

The number of the series of sections sh own in the diagram could be decreased to a single section or. to as many sections as may be desired as this depends upon the load, upon'the rate of the charging current and the capacity of the electrolytic condensers.

Similarly, the load voltage can be varied for any condition by merely increasing the charging voltage and the number of electrolyticv condenser cells per branch. It is obvious that a combination circuit for providing both a high voltage and a low voltage can be arranged and operated from the same transformer byproperly arranging a pair of circuits, each of which co'uldhave its own rectifier suitable for the voltage desired and the proper number of electrolytic cells for each electrolytic condenser E. This arrangement makes it possible to supply two constant currents of different voltages.

It is desirable to charge the electrolytic condensers at a slightly greater rate than the discharge which takes place at the load H. I believe that the system will failto function properly if the rate of discharge is greater than the charging rate. .If the charging rate is considerably greater than the discharge rate at the load H, the system becomes unstable and may cause disturbances at the load H.

. The value of the inductances'L L L L L and L depends upon the frequency of the current supplied'to the transformer.

In all cases I prefer that there should be an inductance on both branches of the line prior to entering the apparatus at the load H.

While I do not wish to limit myself to any specific theory of operation, the correct theory of operation of the above mentioned alternating or pulsating currents of various frequencies which are higher than the frequency of the load current." These high frequency pulsating or alternating currents have been heretofore suppressed by the use essarily expensive and bulky.

However, according to my invention the load component passes readily through the low resistance of the inductanees to the load H while the alternating currents are shunted to the condensers G. Since the'condense-rs C are grounded at the points G there will be a capacity. current to the ground from each .of filters so that an apparatus which accolnplished the purposes herein desired was neccondenser O, for each pulsation of the charging current. If the load current is pulsating' it charges the condensers E, which have greater capacities than the condensers C, so that the action of condensers E and the ind'uctances changes the pulsating load.eom-

ponent or current to direct current.

Thus, it has been found that when each of the coils L L etc., has an inductance of two henries, that each of the condensers E should have a capacity of 20 microfarads and each of the condensers C should have a capacity of one (1) microfarad.

Hence,.by having a sufiicient number of sections the undesirable high frequency a pulsating com onents of the current trans mitted throng the rectifier R are dissipated by means of the-high impedance and the leakage currents so that the load I-I receives substantially bnly a direct current.

The reason for the use of the electrolytic condensers E is because they are of lar e capacity but said condensers E could e replaced by electrostatic condensers of sufiiciently. large capacity. without departing from my invention.

Similarly, I can increase the load com- I ponent of the current transmitted through the rectifier R by having the various .in-

ductances rovided with air cores and providing eac inductance with suflicient turns to supply the necessary impedance. The

increase 1n the resistance thus produced can be taken care of by simply: increasing thev voltage supplied bythe secondary winding. I have describeda preferred embodiment of my invention but it-is clear that numerous changes and omissions could be made without departing from its spirit, ,and I believe and claim that my invention is-pioneer in I claim: l 1. A circuit including a plurality of mains, a load connected to one end of said mains,

a source of current connected to the other end of said mains andadapted to deliver a comyplex currenthaving a load component and a nonload component of higher frequency than said load component, impedance means connected in series with said mains, relativcly large capacity means connected in shunt withsaid mains and between sets of said impedance means, relatively small capacity means connected in shunt with said mains between other sets of said impedance means, and connections leading from a midpoint in each of said relatively small capac.-. ity means-to ground. .v

2 A circuit for eliminating undesired of small capacities havi connections signature.

electrical pulsations comprising in combina- A tion with 'a source of pulsating current, a

air of lines, inductances connected in series an each of said lines and a plurality of branch circuits connected in shunt with said lines across pointsIbetween said inductances, alternate ones of said branch circuits in eluding high capacity devices and adjacent ones of sai thereof connected to groun' 3. A circuit lines across points between said inductances,

an electrolytic condens nate branch circuits,

including sald electrolytic cdndensers, and 1 from points intermediate said I small capacities to ground.-

. In testimony 'whereofI hereunto" my branch circuits including a pair the midpoints for eliminating undesired electrical'pulsations comprising in combination with asource of pulsating current, a .pair of lines, inductances connected in series er connected in alters) v A a pair of relatively small capacities disposed in alternate branch circuits adjacent each ofthe branch circuits 

